Hello, World!
The obligatory "Hello, World!", but it's a pretty cool design and implementation that you will really love. That's because it's a service that demonstrates the reactive platform components.
Last updated
The obligatory "Hello, World!", but it's a pretty cool design and implementation that you will really love. That's because it's a service that demonstrates the reactive platform components.
Last updated
The xoom-helloworld
example is a pinned repository on our . To use to it learn, first clone the repository and build the project. Open a console/command window so you can build the xoom-helloworld
artifact and start it by executing the built jar
file.
The above java
command executes the jar
on the default port 18080
. If you would like to use a different port, you must provide it on the command line. This command uses port 8080
.
The following examples assume that you have started the service with the default port, 18080
.
There are two resources, each with multiple endpoints. These are discussed next.
The first resource is used to get "Hello, World!"
and similar messages.
You may curl
with GET
methods on the following resources.
The above curl
responds with 200 OK
and the content body entity "Hello, World!"
You may also provide a path parameter to indicate to whom the service should say "Hello"
. The second example responds with 200 OK
and the content body entity "Hello, Me!"
The second resource is a bit more involved, and is used to maintain any number of Greeting
messages. These greetings have the following data associated with them.
id
: a unique identity
message
: a text message
messageChangedCount
: the number of times the message text has changed since first being defined
description
: a text description of the message
descriptionChangedCount
: the number of times the description text has changed since first being defined
The first operation used is to define a new Greeting
. To do so you POST
a JSON
object to the /greetings
URI.
The resource will respond with (only the id could be different):
Following this you may query the new Greeting
. The Location
of the new Greeting
resource is /greetings/{someId}
. Let's GET
that resource.
You should see the following:
Next PATCH
the Greeting
resource's message
.
The resource responds with the following. Note that the message
has changed to "Yo"
, and the messageChangedCount
is now 1
. Also notice that the description
and the descriptionChangedCount
remain unchanged.
Next PATCH
the Greeting
resource's description
.
The resource responds with the following. Note that the description
has changed to "Says Yo"
, and the descriptionChangedCount
is now 1
.
Now both the message
and the description
and the corresponding counts have all changed.
In this Greeting
resource example there are various component sets involved. See the following source code.
Documentation for the above components is found in the following links.
In this Hello resource example there is only one component involved,.